Such an analysis apparatus is intended in particular for detecting and measuring incipient phenomena of phase separation, sedimentation in particular into various mixtures. The mixtures concerned are mixtures in which singularities or discontinuities (liquid, solid or gaseous, or a combination) are dispersed in a continuous medium of a different composition and/or state. For example, this concerns emulsions if two or more liquid phases are mixed or suspensions if solid particles are dispersed in a liquid. There are numerous fields of application for such an apparatus. The chemical and para-chemical industries are the main fields, but such devices can be used in any field where it is necessary to analyze the structure and/or stability of a multiphase mixture.
Document EP-0,760,092 discloses an apparatus for performing an analysis of a sample of a multiphase mixture. The method described therein and the corresponding device allow conducting an optical analysis of a mixture and are ideal for characterizing the stability of a mixture, for example a concentrated liquid dispersion.
The method described in that document of the prior art consists of emitting a light beam through a sample of the multiphase mixture and measuring the light that is backscattered and potentially transmitted all along the height of the sample. In this manner, it is possible to detect variations in size (coalescence, flocculation) and phase separations (sedimentation, creaming) of the mixture analyzed.
Systems that use this method currently only permit analysis of a single sample. There are “loaders” of course, which manipulate samples stored in a storage unit, preferably temperature regulated, to bring them one after another to the associated analysis device. The main drawback of this combination of analysis device and loader is related to sample transport. The transport act has some impact, even if carried out carefully, and may for example lead to dispersions in areas where the destabilization phenomenon is more visible and thus mask the phenomenon of interest. Another drawback is the cost of the loader, because it must be precise and carry the samples with very little shaking. In addition, its price increases rapidly with the number of samples to be handled.
Also known from documents U.S. Pat. No. 6,388,751 and FR-2 453 405 are devices for analyzing a plurality of samples placed in tubes. Several tubes are arranged in a vertical position next to one another and an analysis head moves horizontally in front of each of the tubes in order to obtain a measurement at a given height. These devices are not suitable for phase analysis of a multiphase mixture.
Document EP-2 144 051 provides a storage rack adapted for an analysis device. The rack is designed to hold tubes each containing a sample and arranged vertically. A reading head is moved on an arm in two horizontal directions, and in one vertical direction. The reading head here has three degrees of freedom. Aside from the complexity of this device, it is difficult to ensure precise positioning of the sample relative to the reading head, and in the case of phase analysis of a multiphase mixture, to obtain repeatability in the measurement results.